Stop lamp/brake light

[JeffM]

Hi all, it has been a while.
I am in need of your collective problem solving abilities.
Some may recall i do not do electrics well (not sure how they get the smoke in the plastic thingy)so it is with anticipation that i hope you can help.

Firstly 2008 K9 with WP converted to Aussie spec (minor detail).

I have my front brake fire cracker positioned so the brake lite does NOT come on as vibrations sets it off.
My rear brake system has had a full rebuild and has been working fine but i noticed that both the wires to the new pressure switch has power and that my brake lite stays on continually.
Why is this so?
I have tried 3 pressures switches, same result. I have a relay with a fuse installed during WP install so i replaces it as well, same same.

Please Help.

 

[Sven]

3 switches can't be all bad, right? Maybe 1, but how about that front brake light might be on and this is throwing you off? is the front brake pin adjustable as in to push the pin in more via the screw mount has a slot?

 

[JeffM]

Valid point Sven.
Maybe i will try and put a bigger gap in the front brake.
I guess it is going to come down to elimination.
I did note that the new relay was warm while i was charging the battery.
Direct short me thinks ................anyone??

 

[Sven]

Pull relay then install the relay [in the dark]... Did the relay spike at the connection? If so, then a short. Key off, battery being charged, now pull connectors off for a spike to occur.

Which relay? Rely to horn or out of the EFI to fuel pump?

 

[JeffM]

No spike or even a spark.
The guy who installed my WP put a relay on the brake circuit only. Don't know why. Been working fine for 2 years.
Will pull the front brake down now.

 

[JeffM]

After pulling the right control off i found i had completely removed the magnet (firecracker) taped it up and shoved it inside the bars.
I tracked a wire to the relay that is live with the ignition off, so i have pulled that for the present.
A auto electrician is calling by later today, with the view of me putting one of his kids through private school.
$150 for the call out and $150/hour or part there of.
I have also found my 12mth old Braille battery is dead after 24 hours of charging, another cost.

Love my Dog, but running out of kids to sell for scientific experiments to keep it on the road.
May have to put the wife up for sale.

 

[JeffM]

Just back home from work, checked the progress off this post..............nothing in 3 weeks.

I have installed the new HD battery, but my auto sparky mate got sick and did not front.

Still have constant power to the rear brake lite as if the brake is on at all times.

Is my WP unit fried?
Can i bypass this somehow?

Anyone?

 

[Jwooky]

Step back and make some simple checks.

The brake switches are normally open, and close when you apply the brakes. You can easily verify they are open with a continuity check.

With WP, both front and rear switches are spliced together, and they switch to ground. If either circuit is touching the frame or metal they will activate. There should not be a relay.

If both sides have power, either the switch is closed, or the wires are shorted together.

 

[JeffM]

Thanks for the reply.
Done all that, as for the relay the guy who installed the WP said it required it to do "something".
It has worked fine for 2 years.
If i have new brake line, master and slave cylinders renewed with kits, new brake pads, system bleed.
Hand brake magnet not contacting anything.

Why do i have something telling my brake light to come on.
Could it be the board at the front brake?
Could there be a ground wire touching? if so where?

 

[Jwooky]

Guess I'm confused, you say you've done all that, then you follow up by asking what's telling the brake to come on?

What were the results of the continuity test in the front and rear bake switches?

Do the results change if you unplug them?

The schematic is fairly simple. Each switch has two wires. One goes to ground, the other goes back to the WP module.

At least that is how it should be done. I can't really speak for the relay that was added. It may have been added to separate the turn and brake function. In that case it could be hard wired through the relay. Only guessing without seeing it or a schematic of it.

 

[JeffM]

Thanks JJ, sorry for the confusion. I know very little about the smoke that lives inside the red and black plastic, give me a lathe or a welder and i will make whatever you want.

Ok , have disconnected the front brake so it does not work (on purpose), the back brake has 2 wires running to the pressure switch both wires have "power". Shouldn't one be a ground the other power?
When i reconnect the wires to the rear brake the brake lite comes on constantly - regardless of whether the pedal is pushed.
As for a continuity check what is that?
If i unplug the back brake at the relay or anywhere else i still have power to the the relay saying the brake pedal is pushed.
Does this make sense?
I suppose i am concerned i have done a WP unit.
With know one within 300 miles able to assist this is an issue.

 

[francoblay1]

Thanks for the reply.
Done all that, as for the relay the guy who installed the WP said it required it to do "something".
It has worked fine for 2 years.
If i have new brake line, master and slave cylinders renewed with kits, new brake pads, system bleed.
Hand brake magnet not contacting anything.

Why do i have something telling my brake light to come on.
Could it be the board at the front brake?
Could there be a ground wire touching? if so where?

Jeff, just a thought....

That front brake magnet is a PROXIMITY Magnet, it does not need to make contact for the Brake Lights to work...... check it out.

 

[BWG56]

Jeff, just a thought....

That front brake magnet is a PROXIMITY Magnet, it does not need to make contact for the Brake Lights to work...... check it out.

Man, look at you boy, gettin all sophisticated on us with those big words
The switch is a proximity switch which needs ferrous material for it to activate. Aluminum and plastic for instance is non-ferrous.

 

[chubs]

Man, look at you boy, gettin all sophisticated on us with those big words
The switch is a proximity switch which needs ferrous material for it to activate. Aluminum and plastic for instance is non-ferrous.

Now Ker, you know what a magnet is. (it's like Big Dogs are chick magnets) See now, that wasn't such a big word!

 

[francoblay1]

 

[JeffM]

Guys you may be on to something here. I will disconnect the aforementioned "magnet" completely and see what that does.
It still puzzles me that everything has worked fine since the WP install over 2 years ago.
Maybe the vibration from this jackhammer has done something to cause a point of contact.
Cheers

 

[Th3InfamousI]

Unplug the front brake reed switch wire from the right hand PCB and see if the brake light is still on. If it is we know it's not the magnet.

I still don't understand what this additional relay is for? Is it bypassing the WP completely??

Sent from my 831C using Tapatalk

 

[JeffM]

v

Unplug the front brake reed switch wire from the right hand PCB and see if the brake light is still on. If it is we know it's not the magnet.

I still don't understand what this additional relay is for? Is it bypassing the WP completely??

Sent from my 831C using Tapatalk

Unplug the front brake reed switch wire from the right hand PCB and see if the brake light is still on. If it is we know it's not the magnet.

I still don't understand what this additional relay is for? Is it bypassing the WP completely??

Sent from my 831C using Tapatalk

I don't either. The guy who did the install has degrees in electrical engineering so I didn't argue.

 

[JeffM]

v


I don't either. The guy who did the install has degrees in electrical engineering so I didn't argue.

Front brake firecracker pulled out and held 4"away. No difference brake light still on

 

[MossBerg590]

If you have the old style pcb where the switch is soldered rather than plug in type, check closely right where wires ho into board. They wear right there easily and may be shorting out